Troubleshooting an HC emissions failure, slightly rough idle on a distributor ignition system, 94 Chevy Suburban 5.7 liter. There's an electronic ignition module that fires the coil. It was replaced a few weeks ago along with the coil, plug wires, and plugs; the old one was misfiring horribly. Pickup coil's never been changed in 360K miles. The dwell period before the spark occurs seems to be divided into 2 sections. The first section looks like the one I expect, but there's only a slight blip when the primary is grounded, and then it takes another 2.5 msec or so before the spark actually fires. Seems to me that the spark should have occurred as soon as the primary was grounded. ??
- pri and sec.psdata
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